All C header files from the top-level directory of the distribution are now installed on VMS,
providing consistency with a long-standing practice on other platforms.
Previously only a subset were installed,
which broke non-core extension builds for extensions that depended on the missing include files.

A regression introduced in Perl v5.16.0 involving tr/SEARCHLIST/REPLACEMENTLIST/ has been fixed.
Only the first instance is supposed to be meaningful if a character appears more than once in SEARCHLIST.
Under some circumstances,
the final instance was overriding all earlier ones.
[perl #113584]

B::COP::stashlen has been added.
This provides access to an internal field added in perl 5.16 under threaded builds.
It was broken at the last minute before 5.16 was released [perl #113034].

Unicode 6.1 published an incorrect alias for one of the Canonical_Combining_Class property's values (which range between 0 and 254).
The alias CCC133 should have been CCC132.
Perl now overrides the data file furnished by Unicode to give the correct value.

Duplicating scalar filehandles works again.
[perl #113764]

Under threaded perls,
a runtime code block in a regular expression could corrupt the package name stored in the op tree,
resulting in bad reads in caller,
and possibly crashes [perl #113060].

For efficiency's sake,
many operators and built-in functions return the same scalar each time.
Lvalue subroutines and subroutines in the CORE:: namespace were allowing this implementation detail to leak through.
print &CORE::uc("a"),
&CORE::uc("b") used to print "BB".
The same thing would happen with an lvalue subroutine returning the return value of uc.
Now the value is copied in such cases [perl #113044].

__SUB__ now works in special blocks (BEGIN,
END,
etc.).

Formats that reference lexical variables from outside no longer result in crashes.

The list above is almost certainly incomplete as it is automatically generated from version control history.
In particular,
it does not include the names of the (very much appreciated) contributors who reported issues to the Perl bug tracker.

Many of the changes included in this version originated in the CPAN modules included in Perl's core.
We're grateful to the entire CPAN community for helping Perl to flourish.

For a more complete list of all of Perl's historical contributors,
please see the AUTHORS file in the Perl source distribution.

If you find what you think is a bug,
you might check the articles recently posted to the comp.lang.perl.misc newsgroup and the perl bug database at http://rt.perl.org/perlbug/ .
There may also be information at http://www.perl.org/ ,
the Perl Home Page.

If you believe you have an unreported bug,
please run the perlbug program included with your release.
Be sure to trim your bug down to a tiny but sufficient test case.
Your bug report,
along with the output of perl -V,
will be sent off to perlbug@perl.org to be analysed by the Perl porting team.

If the bug you are reporting has security implications,
which make it inappropriate to send to a publicly archived mailing list,
then please send it to perl5-security-report@perl.org.
This points to a closed subscription unarchived mailing list,
which includes all the core committers,
who will be able to help assess the impact of issues,
figure out a resolution,
and help co-ordinate the release of patches to mitigate or fix the problem across all platforms on which Perl is supported.
Please only use this address for security issues in the Perl core,
not for modules independently distributed on CPAN.